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#ifndef Q3DSDISTANCEFIELDGLYPHCACHE_P_H
#define Q3DSDISTANCEFIELDGLYPHCACHE_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtQuick/private/qsgadaptationlayer_p.h>
#include "render/Qt3DSRenderTexture2D.h"
#include "Qt3DSRenderContextCore.h"

#if QT_VERSION >= QT_VERSION_CHECK(5,12,2)

QT_BEGIN_NAMESPACE

class QSGAreaAllocator;
class Q3DSDistanceFieldGlyphCache : public QSGDistanceFieldGlyphCache
{
public:
    struct TextureInfo {
        qt3ds::render::NVRenderTexture2D *texture;
        int padding = -1;

        QRect allocatedArea;
        QImage copy;
    };

    Q3DSDistanceFieldGlyphCache(const QRawFont &font,
                                qt3ds::render::IQt3DSRenderContext &context);
    ~Q3DSDistanceFieldGlyphCache() override;

    void requestGlyphs(const QSet<glyph_t> &glyphs) override;
    void storeGlyphs(const QList<QDistanceField> &glyphs) override;
    void referenceGlyphs(const QSet<glyph_t> &glyphs) override;
    void releaseGlyphs(const QSet<glyph_t> &glyphs) override;

    void processPendingGlyphs() override;

    TextureInfo *textureInfoById(uint textureId) const;

    qreal fontSize() const;

private:
    bool loadPregeneratedCache(const QRawFont &font);
    TextureInfo *textureInfo(int index) const;

    int maxTextureSize() const;
    void resizeTexture(TextureInfo *info, int width, int height);
    void setTextureData(qt3ds::render::NVRenderTexture2D *texture, QImage &image);

    QSGAreaAllocator *m_areaAllocator = nullptr;
    int m_maxTextureSize              = 0;
    int m_maxTextureCount             = 3;

    mutable QVector<TextureInfo> m_textures;
    QHash<glyph_t, TextureInfo *> m_glyphsTexture;
    QSet<glyph_t> m_unusedGlyphs;
    qt3ds::render::IQt3DSRenderContext &m_context;
};

QT_END_NAMESPACE

#endif // Q3DSDISTANCEFIELDGLYPHCACHE_P_H

#endif // QT_VERSION >= QT_VERSION_CHECK(5,12,2)